In the past, it has been recognized that high voltage power lines, which generate substantial electrical fields, make repair work extremely difficult. Power lines of this type extend over remote areas that are inaccessible to land vehicles, and the techniques for reaching and servicing these remote high voltage power lines have often been economically disadvantageous, cumbersome and operationally undesirable. To alleviate some of these disadvantages, helicopters provided with associated work platforms mounted directly to the helicopter skid tubes have been devised for supporting a lineman who can then perform the necessary work on a high voltage power line from the hovering helicopter. A system of this type is illustrated by U.S. Pat. No. 4,637,575 to Scott H. Yenzer.
High voltage power lines are especially difficult to inspect and repair in remote areas during winter weather, as a thick coating of ice and snow will often accumulate on the power lines. This can be destructive in that it does damage to conductors and also damage to structures due to the weight of the ice. Removal of this ice and snow accumulation might be accomplished by a lineman supported by the prior art helicopter work platform who manually manipulates a spray nozzle to spray a deicing or anti-icing compound onto the high voltage power line. Prior art spray systems, such as that illustrated in U.S. Pat. No. 4,477,289 to Kurtgis, require that a helicopter fly extremely close to a power line and individually attempt to spray each individual line which is both somewhat hazardous and time consuming. Not only is it difficult to adequately spray each line in a multi-line system but a lineman must be exposed to the elements in order to control the sprayer. This is totally unsatisfactory in cold, windy weather conditions, for the time that a lineman can remain exposed is extremely limited.
Known aircraft borne spray systems, such as those illustrated by U.S. Pat. No. 2,493,017 to Nutter, U.S. Pat. No. 3,410,489 to Waldrum, and U.S. Pat. No. 3,920,184 to Waldrum, are designed to spray material under pressure over wide areas, and these systems do not provide the concentration of material in a very limited and defined area occupied by a power line system to adequately protect the power lines against icing.
Consequently, a need has arisen for a helicopter anti-icing and deicing system and method which operates safely, rapidly and effectively to apply anti-icing or deicing fluid to a multiple power line system without requiring human exposure to the elements.